A 5′-acyloxynucleoside compound represented by the formula
wherein R1 is an acyl group and R4 is
wherein X is a hydrogen atom, a halogen atom, an amino group, an alkyl group, an aralkyl group, a substituted amino group or a hydroxyl group, and Y is a hydrogen atom, a halogen atom, an alkyl group, an aralkyl group or an aryl group is useful for the production of a deoxynucleic acid derivative and the like.
As a production method of the 5′-acyloxynucleoside compound, for example, a method comprising protecting hydroxyl groups at the 2- and 3-positions with isopropylidene groups and the like, protecting a hydroxyl group at the 5′-position with an acyl group such as benzoyl group, acetyl group and the like, and removing isopropylidene groups has been reported (Tetrahedron, vol. 46, No. 9, p. 3101 (1990), and Tetrahedron, vol. 23, No. 5, pp. 2301-313 (1967)). This method is problematic in that the operation is complicated and the number of steps is many.
In addition, a method comprising selective deacylation of a nucleic acid derivative (nucleoside) with hydroxylamine acetate/pyridine (Journal of the Chemical Society Perkin Transaction, pp. 563-573 (1980)), and a method comprising selective debenzoylation of a nucleic acid derivative with tetrahydrofuran/sodium methoxide (Tetrahedron, No. 41, vol. 23, pp. 5503-5506 (1985) have been reported. These methods are problematic in that a pyridine adduct is by-produced in the former and a methoxy form is by-produced in the latter, which markedly degrades the yield.
Thus, there is a demand for a method for conveniently producing a 5′-acyloxynucleoside compound in a good yield while suppressing formation of by-products.